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More ACPI updates for 4.20-rc1

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Rework the handling of the P-unit semaphore on Intel Baytrail and
 Cherrytrail systems to avoid race conditions and excessive overhead
 related to it (Hans de Goede).
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Merge tag 'acpi-4.20-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more ACPI updates from Rafael Wysocki:
 "Rework the handling of the P-unit semaphore on Intel Baytrail and
  Cherrytrail systems to avoid race conditions and excessive overhead
  related to it (Hans de Goede)"

* tag 'acpi-4.20-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / PMIC: xpower: Add depends on IOSF_MBI to Kconfig entry
  i2c: designware: Cleanup bus lock handling
  ACPI / PMIC: xpower: Block P-Unit I2C access during read-modify-write
  x86: baytrail/cherrytrail: Rework and move P-Unit PMIC bus semaphore code
This commit is contained in:
Linus Torvalds 2018-10-30 09:15:31 -07:00
commit c2101d0182
8 changed files with 250 additions and 183 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
arch/x86/include/asm/iosf_mbi.h
View File

@ -105,8 +105,10 @@ int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask);
* the PMIC bus while another driver is also accessing the PMIC bus various bad
* things happen.
*
* To avoid these problems this function must be called before accessing the
* P-Unit or the PMIC, be it through iosf_mbi* functions or through other means.
* Call this function before sending requests to the P-Unit which may make it
* access the PMIC, be it through iosf_mbi* functions or through other means.
* This function will block all kernel access to the PMIC I2C bus, so that the
* P-Unit can safely access the PMIC over the shared I2C bus.
*
* Note on these systems the i2c-bus driver will request a sempahore from the
* P-Unit for exclusive access to the PMIC bus when i2c drivers are accessing
@ -122,6 +124,31 @@ void iosf_mbi_punit_acquire(void);
*/
void iosf_mbi_punit_release(void);
/**
* iosf_mbi_block_punit_i2c_access() - Block P-Unit accesses to the PMIC bus
*
* Call this function to block P-Unit access to the PMIC I2C bus, so that the
* kernel can safely access the PMIC over the shared I2C bus.
*
* This function acquires the P-Unit bus semaphore and notifies
* pmic_bus_access_notifier listeners that they may no longer access the
* P-Unit in a way which may cause it to access the shared I2C bus.
*
* Note this function may be called multiple times and the bus will not
* be released until iosf_mbi_unblock_punit_i2c_access() has been called the
* same amount of times.
*
* Return: Nonzero on error
*/
int iosf_mbi_block_punit_i2c_access(void);
/*
* iosf_mbi_unblock_punit_i2c_access() - Release PMIC I2C bus block
*
* Release i2c access block gotten through iosf_mbi_block_punit_i2c_access().
*/
void iosf_mbi_unblock_punit_i2c_access(void);
/**
* iosf_mbi_register_pmic_bus_access_notifier - Register PMIC bus notifier
*
@ -158,14 +185,6 @@ int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb);
int iosf_mbi_unregister_pmic_bus_access_notifier_unlocked(
struct notifier_block *nb);
/**
* iosf_mbi_call_pmic_bus_access_notifier_chain - Call PMIC bus notifier chain
*
* @val: action to pass into listener's notifier_call function
* @v: data pointer to pass into listener's notifier_call function
*/
int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v);
/**
* iosf_mbi_assert_punit_acquired - Assert that the P-Unit has been acquired.
*/

217
arch/x86/platform/intel/iosf_mbi.c
View File

@ -18,24 +18,26 @@
* enumerate the device using PCI.
*/
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/pci.h>
#include <linux/debugfs.h>
#include <linux/capability.h>
#include <linux/pm_qos.h>
#include <asm/iosf_mbi.h>
#define PCI_DEVICE_ID_BAYTRAIL 0x0F00
#define PCI_DEVICE_ID_BRASWELL 0x2280
#define PCI_DEVICE_ID_QUARK_X1000 0x0958
#define PCI_DEVICE_ID_TANGIER 0x1170
#define PCI_DEVICE_ID_INTEL_BAYTRAIL 0x0F00
#define PCI_DEVICE_ID_INTEL_BRASWELL 0x2280
#define PCI_DEVICE_ID_INTEL_QUARK_X1000 0x0958
#define PCI_DEVICE_ID_INTEL_TANGIER 0x1170
static struct pci_dev *mbi_pdev;
static DEFINE_SPINLOCK(iosf_mbi_lock);
static DEFINE_MUTEX(iosf_mbi_punit_mutex);
static BLOCKING_NOTIFIER_HEAD(iosf_mbi_pmic_bus_access_notifier);
/**************** Generic iosf_mbi access helpers ****************/
static inline u32 iosf_mbi_form_mcr(u8 op, u8 port, u8 offset)
{
@ -192,6 +194,30 @@ bool iosf_mbi_available(void)
}
EXPORT_SYMBOL(iosf_mbi_available);
/*
**************** P-Unit/kernel shared I2C bus arbritration ****************
*
* Some Bay Trail and Cherry Trail devices have the P-Unit and us (the kernel)
* share a single I2C bus to the PMIC. Below are helpers to arbitrate the
* accesses between the kernel and the P-Unit.
*
* See arch/x86/include/asm/iosf_mbi.h for kernel-doc text for each function.
*/
#define SEMAPHORE_TIMEOUT 500
#define PUNIT_SEMAPHORE_BYT 0x7
#define PUNIT_SEMAPHORE_CHT 0x10e
#define PUNIT_SEMAPHORE_BIT BIT(0)
#define PUNIT_SEMAPHORE_ACQUIRE BIT(1)
static DEFINE_MUTEX(iosf_mbi_punit_mutex);
static DEFINE_MUTEX(iosf_mbi_block_punit_i2c_access_count_mutex);
static BLOCKING_NOTIFIER_HEAD(iosf_mbi_pmic_bus_access_notifier);
static u32 iosf_mbi_block_punit_i2c_access_count;
static u32 iosf_mbi_sem_address;
static unsigned long iosf_mbi_sem_acquired;
static struct pm_qos_request iosf_mbi_pm_qos;
void iosf_mbi_punit_acquire(void)
{
mutex_lock(&iosf_mbi_punit_mutex);
@ -204,6 +230,159 @@ void iosf_mbi_punit_release(void)
}
EXPORT_SYMBOL(iosf_mbi_punit_release);
static int iosf_mbi_get_sem(u32 *sem)
{
int ret;
ret = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ,
iosf_mbi_sem_address, sem);
if (ret) {
dev_err(&mbi_pdev->dev, "Error P-Unit semaphore read failed\n");
return ret;
}
*sem &= PUNIT_SEMAPHORE_BIT;
return 0;
}
static void iosf_mbi_reset_semaphore(void)
{
if (iosf_mbi_modify(BT_MBI_UNIT_PMC, MBI_REG_READ,
iosf_mbi_sem_address, 0, PUNIT_SEMAPHORE_BIT))
dev_err(&mbi_pdev->dev, "Error P-Unit semaphore reset failed\n");
pm_qos_update_request(&iosf_mbi_pm_qos, PM_QOS_DEFAULT_VALUE);
blocking_notifier_call_chain(&iosf_mbi_pmic_bus_access_notifier,
MBI_PMIC_BUS_ACCESS_END, NULL);
}
/*
* This function blocks P-Unit accesses to the PMIC I2C bus, so that kernel
* I2C code, such as e.g. a fuel-gauge driver, can access it safely.
*
* This function may be called by I2C controller code while an I2C driver has
* already blocked P-Unit accesses because it wants them blocked over multiple
* i2c-transfers, for e.g. read-modify-write of an I2C client register.
*
* The P-Unit accesses already being blocked is tracked through the
* iosf_mbi_block_punit_i2c_access_count variable which is protected by the
* iosf_mbi_block_punit_i2c_access_count_mutex this mutex is hold for the
* entire duration of the function.
*
* If access is not blocked yet, this function takes the following steps:
*
* 1) Some code sends request to the P-Unit which make it access the PMIC
* I2C bus. Testing has shown that the P-Unit does not check its internal
* PMIC bus semaphore for these requests. Callers of these requests call
* iosf_mbi_punit_acquire()/_release() around their P-Unit accesses, these
* functions lock/unlock the iosf_mbi_punit_mutex.
* As the first step we lock the iosf_mbi_punit_mutex, to wait for any in
* flight requests to finish and to block any new requests.
*
* 2) Some code makes such P-Unit requests from atomic contexts where it
* cannot call iosf_mbi_punit_acquire() as that may sleep.
* As the second step we call a notifier chain which allows any code
* needing P-Unit resources from atomic context to acquire them before
* we take control over the PMIC I2C bus.
*
* 3) When CPU cores enter C6 or C7 the P-Unit needs to talk to the PMIC
* if this happens while the kernel itself is accessing the PMIC I2C bus
* the SoC hangs.
* As the third step we call pm_qos_update_request() to disallow the CPU
* to enter C6 or C7.
*
* 4) The P-Unit has a PMIC bus semaphore which we can request to stop
* autonomous P-Unit tasks from accessing the PMIC I2C bus while we hold it.
* As the fourth and final step we request this semaphore and wait for our
* request to be acknowledged.
*/
int iosf_mbi_block_punit_i2c_access(void)
{
unsigned long start, end;
int ret = 0;
u32 sem;
if (WARN_ON(!mbi_pdev || !iosf_mbi_sem_address))
return -ENXIO;
mutex_lock(&iosf_mbi_block_punit_i2c_access_count_mutex);
if (iosf_mbi_block_punit_i2c_access_count > 0)
goto success;
mutex_lock(&iosf_mbi_punit_mutex);
blocking_notifier_call_chain(&iosf_mbi_pmic_bus_access_notifier,
MBI_PMIC_BUS_ACCESS_BEGIN, NULL);
/*
* Disallow the CPU to enter C6 or C7 state, entering these states
* requires the P-Unit to talk to the PMIC and if this happens while
* we're holding the semaphore, the SoC hangs.
*/
pm_qos_update_request(&iosf_mbi_pm_qos, 0);
/* host driver writes to side band semaphore register */
ret = iosf_mbi_write(BT_MBI_UNIT_PMC, MBI_REG_WRITE,
iosf_mbi_sem_address, PUNIT_SEMAPHORE_ACQUIRE);
if (ret) {
dev_err(&mbi_pdev->dev, "Error P-Unit semaphore request failed\n");
goto error;
}
/* host driver waits for bit 0 to be set in semaphore register */
start = jiffies;
end = start + msecs_to_jiffies(SEMAPHORE_TIMEOUT);
do {
ret = iosf_mbi_get_sem(&sem);
if (!ret && sem) {
iosf_mbi_sem_acquired = jiffies;
dev_dbg(&mbi_pdev->dev, "P-Unit semaphore acquired after %ums\n",
jiffies_to_msecs(jiffies - start));
/*
* Success, keep iosf_mbi_punit_mutex locked till
* iosf_mbi_unblock_punit_i2c_access() gets called.
*/
goto success;
}
usleep_range(1000, 2000);
} while (time_before(jiffies, end));
ret = -ETIMEDOUT;
dev_err(&mbi_pdev->dev, "Error P-Unit semaphore timed out, resetting\n");
error:
iosf_mbi_reset_semaphore();
mutex_unlock(&iosf_mbi_punit_mutex);
if (!iosf_mbi_get_sem(&sem))
dev_err(&mbi_pdev->dev, "P-Unit semaphore: %d\n", sem);
success:
if (!WARN_ON(ret))
iosf_mbi_block_punit_i2c_access_count++;
mutex_unlock(&iosf_mbi_block_punit_i2c_access_count_mutex);
return ret;
}
EXPORT_SYMBOL(iosf_mbi_block_punit_i2c_access);
void iosf_mbi_unblock_punit_i2c_access(void)
{
mutex_lock(&iosf_mbi_block_punit_i2c_access_count_mutex);
iosf_mbi_block_punit_i2c_access_count--;
if (iosf_mbi_block_punit_i2c_access_count == 0) {
iosf_mbi_reset_semaphore();
mutex_unlock(&iosf_mbi_punit_mutex);
dev_dbg(&mbi_pdev->dev, "punit semaphore held for %ums\n",
jiffies_to_msecs(jiffies - iosf_mbi_sem_acquired));
}
mutex_unlock(&iosf_mbi_block_punit_i2c_access_count_mutex);
}
EXPORT_SYMBOL(iosf_mbi_unblock_punit_i2c_access);
int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb)
{
int ret;
@ -241,19 +420,14 @@ int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL(iosf_mbi_unregister_pmic_bus_access_notifier);
int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v)
{
return blocking_notifier_call_chain(
&iosf_mbi_pmic_bus_access_notifier, val, v);
}
EXPORT_SYMBOL(iosf_mbi_call_pmic_bus_access_notifier_chain);
void iosf_mbi_assert_punit_acquired(void)
{
WARN_ON(!mutex_is_locked(&iosf_mbi_punit_mutex));
}
EXPORT_SYMBOL(iosf_mbi_assert_punit_acquired);
/**************** iosf_mbi debug code ****************/
#ifdef CONFIG_IOSF_MBI_DEBUG
static u32 dbg_mdr;
static u32 dbg_mcr;
@ -338,7 +512,7 @@ static inline void iosf_debugfs_remove(void) { }
#endif /* CONFIG_IOSF_MBI_DEBUG */
static int iosf_mbi_probe(struct pci_dev *pdev,
const struct pci_device_id *unused)
const struct pci_device_id *dev_id)
{
int ret;
@ -349,14 +523,16 @@ static int iosf_mbi_probe(struct pci_dev *pdev,
}
mbi_pdev = pci_dev_get(pdev);
iosf_mbi_sem_address = dev_id->driver_data;
return 0;
}
static const struct pci_device_id iosf_mbi_pci_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_BAYTRAIL) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_BRASWELL) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_QUARK_X1000) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_TANGIER) },
{ PCI_DEVICE_DATA(INTEL, BAYTRAIL, PUNIT_SEMAPHORE_BYT) },
{ PCI_DEVICE_DATA(INTEL, BRASWELL, PUNIT_SEMAPHORE_CHT) },
{ PCI_DEVICE_DATA(INTEL, QUARK_X1000, 0) },
{ PCI_DEVICE_DATA(INTEL, TANGIER, 0) },
{ 0, },
};
MODULE_DEVICE_TABLE(pci, iosf_mbi_pci_ids);
@ -371,6 +547,9 @@ static int __init iosf_mbi_init(void)
{
iosf_debugfs_init();
pm_qos_add_request(&iosf_mbi_pm_qos, PM_QOS_CPU_DMA_LATENCY,
PM_QOS_DEFAULT_VALUE);
return pci_register_driver(&iosf_mbi_pci_driver);
}
@ -381,6 +560,8 @@ static void __exit iosf_mbi_exit(void)
pci_unregister_driver(&iosf_mbi_pci_driver);
pci_dev_put(mbi_pdev);
mbi_pdev = NULL;
pm_qos_remove_request(&iosf_mbi_pm_qos);
}
module_init(iosf_mbi_init);

2
drivers/acpi/Kconfig
View File

@ -512,7 +512,7 @@ config CRC_PMIC_OPREGION
config XPOWER_PMIC_OPREGION
bool "ACPI operation region support for XPower AXP288 PMIC"
depends on MFD_AXP20X_I2C
depends on MFD_AXP20X_I2C && IOSF_MBI
help
This config adds ACPI operation region support for XPower AXP288 PMIC.

21
drivers/acpi/pmic/intel_pmic_xpower.c
View File

@ -8,8 +8,9 @@
#include <linux/acpi.h>
#include <linux/init.h>
#include <linux/mfd/axp20x.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/platform_device.h>
#include <asm/iosf_mbi.h>
#include "intel_pmic.h"
#define XPOWER_GPADC_LOW 0x5b
@ -172,15 +173,21 @@ static int intel_xpower_pmic_get_power(struct regmap *regmap, int reg,
static int intel_xpower_pmic_update_power(struct regmap *regmap, int reg,
int bit, bool on)
{
int data;
int data, ret;
/* GPIO1 LDO regulator needs special handling */
if (reg == XPOWER_GPI1_CTRL)
return regmap_update_bits(regmap, reg, GPI1_LDO_MASK,
on ? GPI1_LDO_ON : GPI1_LDO_OFF);
if (regmap_read(regmap, reg, &data))
return -EIO;
ret = iosf_mbi_block_punit_i2c_access();
if (ret)
return ret;
if (regmap_read(regmap, reg, &data)) {
ret = -EIO;
goto out;
}
if (on)
data |= BIT(bit);
@ -188,9 +195,11 @@ static int intel_xpower_pmic_update_power(struct regmap *regmap, int reg,
data &= ~BIT(bit);
if (regmap_write(regmap, reg, data))
return -EIO;
ret = -EIO;
out:
iosf_mbi_unblock_punit_i2c_access();
return 0;
return ret;
}
/**

139
drivers/i2c/busses/i2c-designware-baytrail.c
View File

@ -3,141 +3,15 @@
* Intel BayTrail PMIC I2C bus semaphore implementaion
* Copyright (c) 2014, Intel Corporation.
*/
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/acpi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/pm_qos.h>
#include <asm/iosf_mbi.h>
#include "i2c-designware-core.h"
#define SEMAPHORE_TIMEOUT 500
#define PUNIT_SEMAPHORE 0x7
#define PUNIT_SEMAPHORE_CHT 0x10e
#define PUNIT_SEMAPHORE_BIT BIT(0)
#define PUNIT_SEMAPHORE_ACQUIRE BIT(1)
static unsigned long acquired;
static u32 get_sem_addr(struct dw_i2c_dev *dev)
{
if (dev->flags & MODEL_CHERRYTRAIL)
return PUNIT_SEMAPHORE_CHT;
else
return PUNIT_SEMAPHORE;
}
static int get_sem(struct dw_i2c_dev *dev, u32 *sem)
{
u32 addr = get_sem_addr(dev);
u32 data;
int ret;
ret = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, addr, &data);
if (ret) {
dev_err(dev->dev, "iosf failed to read punit semaphore\n");
return ret;
}
*sem = data & PUNIT_SEMAPHORE_BIT;
return 0;
}
static void reset_semaphore(struct dw_i2c_dev *dev)
{
if (iosf_mbi_modify(BT_MBI_UNIT_PMC, MBI_REG_READ, get_sem_addr(dev),
0, PUNIT_SEMAPHORE_BIT))
dev_err(dev->dev, "iosf failed to reset punit semaphore during write\n");
pm_qos_update_request(&dev->pm_qos, PM_QOS_DEFAULT_VALUE);
iosf_mbi_call_pmic_bus_access_notifier_chain(MBI_PMIC_BUS_ACCESS_END,
NULL);
iosf_mbi_punit_release();
}
static int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
{
u32 addr;
u32 sem = PUNIT_SEMAPHORE_ACQUIRE;
int ret;
unsigned long start, end;
might_sleep();
if (!dev || !dev->dev)
return -ENODEV;
if (!dev->release_lock)
return 0;
iosf_mbi_punit_acquire();
iosf_mbi_call_pmic_bus_access_notifier_chain(MBI_PMIC_BUS_ACCESS_BEGIN,
NULL);
/*
* Disallow the CPU to enter C6 or C7 state, entering these states
* requires the punit to talk to the pmic and if this happens while
* we're holding the semaphore, the SoC hangs.
*/
pm_qos_update_request(&dev->pm_qos, 0);
addr = get_sem_addr(dev);
/* host driver writes to side band semaphore register */
ret = iosf_mbi_write(BT_MBI_UNIT_PMC, MBI_REG_WRITE, addr, sem);
if (ret) {
dev_err(dev->dev, "iosf punit semaphore request failed\n");
goto out;
}
/* host driver waits for bit 0 to be set in semaphore register */
start = jiffies;
end = start + msecs_to_jiffies(SEMAPHORE_TIMEOUT);
do {
ret = get_sem(dev, &sem);
if (!ret && sem) {
acquired = jiffies;
dev_dbg(dev->dev, "punit semaphore acquired after %ums\n",
jiffies_to_msecs(jiffies - start));
return 0;
}
usleep_range(1000, 2000);
} while (time_before(jiffies, end));
dev_err(dev->dev, "punit semaphore timed out, resetting\n");
out:
reset_semaphore(dev);
ret = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, addr, &sem);
if (ret)
dev_err(dev->dev, "iosf failed to read punit semaphore\n");
else
dev_err(dev->dev, "PUNIT SEM: %d\n", sem);
WARN_ON(1);
return -ETIMEDOUT;
}
static void baytrail_i2c_release(struct dw_i2c_dev *dev)
{
if (!dev || !dev->dev)
return;
if (!dev->acquire_lock)
return;
reset_semaphore(dev);
dev_dbg(dev->dev, "punit semaphore held for %ums\n",
jiffies_to_msecs(jiffies - acquired));
}
int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev)
{
acpi_status status;
@ -162,18 +36,9 @@ int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev)
return -EPROBE_DEFER;
dev_info(dev->dev, "I2C bus managed by PUNIT\n");
dev->acquire_lock = baytrail_i2c_acquire;
dev->release_lock = baytrail_i2c_release;
dev->acquire_lock = iosf_mbi_block_punit_i2c_access;
dev->release_lock = iosf_mbi_unblock_punit_i2c_access;
dev->shared_with_punit = true;
pm_qos_add_request(&dev->pm_qos, PM_QOS_CPU_DMA_LATENCY,
PM_QOS_DEFAULT_VALUE);
return 0;
}
void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev)
{
if (dev->acquire_lock)
pm_qos_remove_request(&dev->pm_qos);
}

4
drivers/i2c/busses/i2c-designware-common.c
View File

@ -269,7 +269,7 @@ int i2c_dw_acquire_lock(struct dw_i2c_dev *dev)
if (!dev->acquire_lock)
return 0;
ret = dev->acquire_lock(dev);
ret = dev->acquire_lock();
if (!ret)
return 0;
@ -281,7 +281,7 @@ int i2c_dw_acquire_lock(struct dw_i2c_dev *dev)
void i2c_dw_release_lock(struct dw_i2c_dev *dev)
{
if (dev->release_lock)
dev->release_lock(dev);
dev->release_lock();
}
/*

9
drivers/i2c/busses/i2c-designware-core.h
View File

@ -10,7 +10,6 @@
*/
#include <linux/i2c.h>
#include <linux/pm_qos.h>
#define DW_IC_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C | \
I2C_FUNC_SMBUS_BYTE | \
@ -209,7 +208,6 @@
* @fp_lcnt: fast plus LCNT value
* @hs_hcnt: high speed HCNT value
* @hs_lcnt: high speed LCNT value
* @pm_qos: pm_qos_request used while holding a hardware lock on the bus
* @acquire_lock: function to acquire a hardware lock on the bus
* @release_lock: function to release a hardware lock on the bus
* @shared_with_punit: true if this bus is shared with the SoCs PUNIT
@ -263,9 +261,8 @@ struct dw_i2c_dev {
u16 fp_lcnt;
u16 hs_hcnt;
u16 hs_lcnt;
struct pm_qos_request pm_qos;
int (*acquire_lock)(struct dw_i2c_dev *dev);
void (*release_lock)(struct dw_i2c_dev *dev);
int (*acquire_lock)(void);
void (*release_lock)(void);
bool shared_with_punit;
void (*disable)(struct dw_i2c_dev *dev);
void (*disable_int)(struct dw_i2c_dev *dev);
@ -322,8 +319,6 @@ static inline int i2c_dw_probe_slave(struct dw_i2c_dev *dev) { return -EINVAL; }
#if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL)
extern int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev);
extern void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev);
#else
static inline int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) { return 0; }
static inline void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev) {}
#endif

2
drivers/i2c/busses/i2c-designware-platdrv.c
View File

@ -418,8 +418,6 @@ static int dw_i2c_plat_remove(struct platform_device *pdev)
if (!IS_ERR_OR_NULL(dev->rst))
reset_control_assert(dev->rst);
i2c_dw_remove_lock_support(dev);
return 0;
}